Optical beam-steering devices and methods utilizing surface scattering metasurfaces

Patent metadata

Field	Value
Publication number	US-10915002-B2
Application number	US-201815900683-A
Country	US
Kind code	B2
Filing date	Feb 20, 2018
Priority date	Feb 22, 2017
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

Systems and methods are described herein for an optical beam-steering device that includes an optical transmitter and/or receiver to transmit and/or receive optical radiation from an optically reflective surface. An array of adjustable dielectric resonator elements is arranged on the surface with inter-element spacings less than an optical operating wavelength. A controller applies a pattern of voltage differentials to the adjustable dielectric resonator elements. The pattern of voltage differentials corresponds to a sub-wavelength reflection phase pattern for reflecting the optical electromagnetic radiation. One embodiment of a dielectric resonator element includes first and second dielectric members extending from the surface. The dielectric resonator elements are spaced from one another to form a gap or channel therebetween. A voltage-controlled adjustable refractive index material is disposed within the gap.

First claim

What is claimed is:

1. An optical beam-steering device, comprising:
an optical electromagnetic radiation converter to convert between electric power and optical electromagnetic radiation;
a surface to reflect the optical electromagnetic radiation;
a plurality of adjustable dielectric resonator elements arranged on the surface with inter-element spacings less than an optical operating wavelength to selectively apply a sub-wavelength reflection phase pattern to the optical electromagnetic radiation.

2. The device of claim 1 , further comprising a controller to selectively apply a pattern of voltages to the plurality of dielectric resonator elements, wherein the pattern of voltages corresponds to a pattern of reflection phases of the plurality of dielectric resonator elements.

3. The device of claim 1 , wherein each of the dielectric resonator elements comprises:
a first dielectric member extending from the surface;
a second dielectric member extending from the surface; and
an adjustable refractive index material disposed in a gap between the first and second dielectric members.

4. The device of claim 3 , wherein the first dielectric member comprises a first elongated wall, the second dielectric member comprises a second elongated wall that is substantially parallel to the first wall, and the adjustable refractive index material is disposed within a channel defined by the first and second walls.

5. The device of claim 4 , wherein each of the first and second elongated walls have a length corresponding to an Nth harmonic mode of frequencies within an optical operating bandwidth, such that N antinodes can be realized along the length of the gap between the first and second elongated walls, where N is an integer.

6. The device of claim 5 , wherein each of the first and second elongated walls extends from the surface to a height corresponding to an Mth order harmonic mode of frequencies within the optical operating bandwidth, such that M antinodes can be realized within the gap between the surface and tops of the first and second elongated walls, where M is an integer.

7. The device of claim 5 , wherein the spacing gap between the first and second elongated walls corresponds to a fundamental harmonic mode of frequencies within the optical operating bandwidth.

8. The device of claim 3 , wherein the first dielectric member comprises a first pillar, the second dielectric member comprises a second pillar, and the adjustable refractive index material is disposed between the first and second pillars.

9. The device of claim 3 , wherein each of the first and second dielectric members extends substantially perpendicular from the surface.

10. The device of claim 3 , further comprising a controller to selectively apply voltage differentials to the first and second dielectric members of each of the dielectric resonator elements, wherein each of a plurality of selectable voltage differentials corresponds to (i) an index of refraction of the adjustable refractive index material, and (ii) a reflection phase of each of the respective dielectric resonator elements.

11. The device of claim 1 , wherein each of the plurality of dielectric resonator elements comprises:
a first dielectric member extending from the surface;
a second dielectric member extending from the surface,
wherein the first dielectric member and the second dielectric member are spaced from one another to form a channel therebetween;

an electrically adjustable refractive index material disposed within at least a portion of the channel; and
electrical contacts to receive an applied voltage differential to the first and second dielectric members,
wherein application of a first voltage differential to the first and second dielectric members corresponds to a first reflection phase, and
wherein application of a second voltage differential to the first and second dielectric members corresponds to a second reflection phase.

12. The device of claim 1 , wherein the optical beam-steering device comprises a transmission device with the optical electromagnetic radiation converter configured to convert electric power into optical electromagnetic radiation.

13. The device of claim 1 , wherein the optical beam-steering device comprises a receiving device with the optical electromagnetic radiation converter configured to convert optical electromagnetic radiation into electric power.

14. The device of claim 1 , wherein the optical beam-steering device comprises a transceiver configured to switch between receiving and transmitting optical electromagnetic radiation.

15. The device of claim 1 , wherein the optical beam-steering device comprises a laser to transmit optical electromagnetic radiation and a photodiode to receive optical electromagnetic radiation.

16. The device of claim 1 , wherein each of the dielectric resonator elements comprises:
a first elongated wall;
a second elongated wall; and
an adjustable refractive index material disposed within a channel defined between the first and second elongated walls.

17. The device of claim 16 , wherein the dielectric resonator elements are arranged in a two-dimensional array.

18. The device of claim 16 , wherein each of the elongated walls extends from the surface to a height between approximately 300 and 1500 nanometers.

19. The device of claim 16 , wherein each of the elongated walls extends from the surface to a height between approximately 500 nanometers.

20. The device of claim 16 , wherein each of the elongated walls has a width between approximately 50 and 300 nanometers.

21. The device of claim 16 , wherein each of the elongated walls has a width of approximately 100 nanometers.

22. The device of claim 16 , wherein each of the elongated walls is spaced from each adjacent elongated wall by between approximately 40 and 250 nanometers.

23. The device of claim 16 , wherein each of the elongated walls is uniformly spaced from each adjacent elongated wall by a spacing distance that is between approximately 50 and 300 nanometers.

24. The device of claim 16 , wherein each of the elongated walls is unevenly spaced from adjacent elongated walls by distances between approximately 50 and 300 nanometers.

25. The device of claim 1 , wherein each of the dielectric resonator elements comprises:
a first pillar having a substantially rectangular base;
a second pillar having substantially rectangular base; and
an adjustable refractive index material disposed between the first and second pillars.

26. The device of claim 25 , wherein each of the first and second pillars are substantially cuboid in shape.

27. The device of claim 26 , wherein a length, height, and width of each of the first and second pillars are based on a target resonance for a wavelength within an operational bandwidth.

28. The device of claim 26 , wherein a length, height, and width of each of the first and second pillars are based on a target resonance and Q factor for a wavelength within an operational bandwidth.

29. The device of claim 26 , wherein each of the first and second pillars extends from the surface to a height between approximately 300 and 1500 nanometers.

Assignees

• Elwha Llc

Inventors

• Akselrod Gleb M

Classifications

• H10W90/00

  Package configurations · CPC title

• H04N25/76

  Addressed sensors, e.g. MOS or CMOS sensors · CPC title

• H04N23/54

  Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils · CPC title

• H10F39/18

  Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors · CPC title

• H10F39/806 Primary

  Optical elements or arrangements associated with the image sensors · CPC title